Clinical Interventions in Aging (Jun 2018)
Ginkgo biloba extract EGb 761® alleviates neurosensory symptoms in patients with dementia: a meta-analysis of treatment effects on tinnitus and dizziness in randomized, placebo-controlled trials
Abstract
Rainer Spiegel,1 Roger Kalla,2 Georgios Mantokoudis,3 Raphael Maire,4 Heiko Mueller,5 Robert Hoerr,5 Ralf Ihl6 1Division of Internal Medicine, Basel University Hospital, University of Basel, Basel, Switzerland; 2Department of Neurology, Inselspital, Bern University Hospital, Bern, Switzerland; 3Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, Bern, Switzerland; 4Lausanne University Hospital, Lausanne, Switzerland; 5Clinical Research Department, Dr Willmar Schwabe GmbH & Co. KG, Karlsruhe, Germany; 6Department of Psychiatry, University of Duesseldorf, Alexian Research Center Krefeld, Krefeld, Germany Background: Tinnitus and dizziness are frequent in old age and often seen as concomitant symptoms in patients with dementia. In earlier clinical trials, Ginkgo biloba extract EGb 761® was found to alleviate tinnitus and dizziness in elderly patients. Consequently, a meta-analysis was conducted to evaluate the effects of EGb 761® at a daily dose of 240 mg on tinnitus and dizziness associated with dementia. Methods: Randomized, placebo-controlled clinical trials of G. biloba extract EGb 761® identified by a systematic database search were included in a meta-analysis if they met all of the following selection criteria: 1) diagnosis of dementia according to generally accepted criteria, 2) treatment period of at least 20 weeks, 3) outcome measures covering at least two of the three conventional domains of assessment, 4) presence and severity of dizziness and tinnitus were assessed, and 5) assessment was done before and after randomized treatment. Results: Five trials that met the inclusion criteria were included in the meta-analysis. The risk of bias was judged as low, with Jadad scores of 3 and 5. In all trials, 11-point box scales were used to assess the severity of tinnitus and dizziness. Overall, EGb 761® was superior to placebo, with weighted mean differences for change from baseline, calculated in meta-analyses using random effects models, of -1.06 (95% CI: -1.77, -0.36) for tinnitus (p = 0.003) and -0.77 (95% CI: -1.44, -0.09) for dizziness (p = 0.03). Conclusion: Our findings support the notion that EGb 761® is also effective in alleviating concomitant neurosensory symptoms in patients with dementia. Keywords: neurodegenerative disorders, gait, unsteadiness, inner ear, hearing, review
